Search results
Results From The WOW.Com Content Network
This helps the cell avoid obstacles and causes other objects to bounce off of the cell's outer membrane. The paramecium does this by reversing the direction in which its cilia beat. This results in stopping, spinning or turning, after which point the paramecium resumes swimming forward. If multiple avoidance reactions follow one another, it is ...
It is not completely known what causes the CV membrane to contract, and whether it is an active process which costs energy or a passive collapse of the CV membrane. Evidence for involvement of actin and myosin, prominent contractile proteins which are found in many cells, are ambiguous. [citation needed] Membrane composition. Although it is ...
Cells are typically ovoid, elongate, or foot- or cigar-shaped. The body of the cell is enclosed by a stiff but elastic structure called the pellicle. The pellicle consists of an outer cell membrane (plasma membrane), a layer of flattened membrane-bound sacs called alveoli, and an inner membrane called the epiplasm. The pellicle is not smooth ...
Most ciliates also have one or more prominent contractile vacuoles, which collect water and expel it from the cell to maintain osmotic pressure, or in some function to maintain ionic balance. In some genera, such as Paramecium , these have a distinctive star shape, with each point being a collecting tube.
Osmoregulation is the active regulation of the osmotic pressure of an organism's body fluids, detected by osmoreceptors, to maintain the homeostasis of the organism's water content; that is, it maintains the fluid balance and the concentration of electrolytes (salts in solution which in this case is represented by body fluid) to keep the body fluids from becoming too diluted or concentrated.
Intracellular transport is required for maintaining homeostasis within the cell by responding to physiological signals. [1] Proteins synthesized in the cytosol are distributed to their respective organelles, according to their specific amino acid’s sorting sequence. [ 2 ]
One main function of plasma and cell membranes is to maintain asymmetric concentrations of inorganic ions in order to maintain an ionic steady state different from electrochemical equilibrium. [8] In other words, there is a differential distribution of ions on either side of the cell membrane - that is, the amount of ions on either side is not ...
Illustration of a eukaryotic cell membrane Comparison of a eukaryotic vs. a prokaryotic cell membrane. The cell membrane (also known as the plasma membrane or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of a cell from the outside environment (the extracellular space).